Stencil sheet



Patented June 21, 1933 I tum'rso STATES PATENT oi-"FlcE EANQBIION, OI HANOVER, GERMANY, ASSIGNOB TO GONG-HEB WAGNER. OI HANOVER, GERMANY, A CORPORATION 01' GERMANY STENCIL SHEET Io Drawing.

This invention relates to improvements in stencil sheets.

Stencil sheets have been prepared by coating lace-like fibrous and porous sheets of 6 paper, such as Japanese Yshin0 paper, with plastic materials impervious to ink. These materials should be of sufiicient softness and plasticity, or should be readily convertible mto such condition as would permit the for- 10 mation of open spaces in said sheet upon pressure, as by typewriter key, through which ink might ass.

Among the p astic materia s advantageously utilized are proteins, such as glue or gelatin, which proteins are preferably suitably hardened, toughened, or coagulated to increase their durability and decrease their tackiness. With such plastic materials it is also desirable 'touse softening a ents, such as glycerin, sugar, fats, oils and atty acids and organic esters as well as filling materials.

of organic or inorganic nature, such as for example wood flour, bentonite and kieselguhr.

These latter materials are desirably utilized to prevent sweating out of the softening materlals and to dec'rease the adhesive properties of the sheet. y

' owever, stencil sheets coatedin this manner are not of as hi h tensile stren h and 80 durability as desirabfie, are influence by adverse weather conditions and particularlytend to deteriorate and moist climates.

Furthermore glycerin, sugar and other 85 polyhydroxy materials are not altogether completely satisfactory as plasticizers. When fat or fatty acid materials were utilrapidly if stored in hot ized whether of animal, vegetable or mineral o'ri in, the coating also is not very durable 40 an tends to be readily influenced by weather conditions. a

An object of this invention is to provide a stencil sheet provided with a plastic 'coatin preferabl consisting of a protein material,

which will be of hi h tensile stren h and of at durability, w ich will not be influenced y adverse weather conditions and which may be stored safely for considerable periods in hot and moist climates.

' A further object is to provide a stencil.

eluding with these I phosphoric acid derivatives, as ingredients in Application 110d August 30, 1982. Serial No. 631,088.

sheet, the coating of which will have the desirable characteristics of a coating plasticized with fats, oils and/or fatty acids without any decrease in durability or liability to be greatly influenced by weather conditions.

In the preferred embodiment of the present invention the above and other objects of the present invention arerealized by employing high molecular alcohols, whether saturated or unsaturated, and ifvdesired, by inalcohols the aromatic the coating.

Among the alcohols which may be used are lauryl alcohol, myricil alcohol, and oleic 66 alcohol. These alcoholsmay be used singly, or in mixtures, preferably with the addition of henolic esters of the phosphoric acid. Alt ough the ali hatic alcohols specifically described are re erred, other high molecular 10 weight alcoho may be employed if of satisfactory properties containing substitnent such as halo en, nitro and aryl radicals, an so forth. the case of high molecular weight aliphatic alcohols, these alcohols may have straight or branch carbon chains, and

-may either 'be saturated or unsaturated.

lic ester of phosphoric ate) has been found to as an additional plats-.

Generally the tricres acid (tric resyl phosp be most satisfactory ticising agent.

To give one specific example of a coating composition, the following composition has been utilized and found to be satisfactory:

Parts by wellht Gelatin 8 Grlyceri'nl 3 Tricresy phosphate 20 Oleic alcohol 10 Myricil alcohol 5 Sulphonated oil 40 good flour 6, igment 10 Dinitrotoluene 0.5 Water This coatin composition may be conveniently applied y brushing or flowin it upon the paper sheet, or by dipping the s eet into anol reierab y it is lit is preferably not of The the Initial coating before drying with gaseous formaldehycle or with a small amount oi a commercial formaldehyde solution. Other coagulating, toughening and hardening agentsmay also be employed.

Other p astic protein or nitrogeneons ma- I terial having similar characteristics to gelatin, and other similar coagulatable materials may also be employecl" alone or in combination with the gelatin. linsteacl of (linitrotoluene, other preserving agents may be employea.

accomplishea by treating,

neraeoe l. A coating for stencil sheets, g

a sulphonated oil, tricresyl phosphate, myricyl alcohol, gelatin, glycerin, We dust, as pigment and a reservative.

2. iii-coating or stencil sheets, comprising tricresyl phosphate, oleic alcohol, gelatin and dinitrotoluene.

3. A coating for stencil sheets, comprising tricresyl phosphate, laur'yl alcohol, gelatin and glycerin.

42. A coating mixture comprising 130 parts by parts by weight of a sul by Weight of tricresyl p weight of nltrama'rine Weight of oleic alcohol, 8 parts by Weight of gelatin, 6 parts by Weight of beechwood flour, 5 parts by Weight myricyl alcohol, 3 parts by weight glycerin, dinitrotoluene.

In testimony whereof I have afixed. my

sigature.

HANS SliMGN.

for making stencils, weight of water, 40 honatecl oil, 20 parts osphate, 10 parts by blue, 10 parts by and. 0.5 parts by weight oi liltl 

